Easy way to allow Embed Code?

It appears that “embed” and other HTML is automatically stripped out of posts for people at the author level. Firstly, why? Using Youtube videos is very common these days, and I trust my Authors. Second, without some costly plugin, how can I allow it? I see that there’s a way in the config to allow certain HTML tags but that seems to allow it in comments too – that’s where i DONT want it allowed. How can it just be allowed for Authors?

Thanks!